Multiple-gas-phase liquid treatment apparatus

ABSTRACT

A multiple-gas-phase liquid treatment apparatus for use, for example, as a gas dissolving apparatus, gas removing apparatus, sewage treatment apparatus, or large-quantity culture apparatus includes a hollow container, a plurality of horizontal partition plates mounted in the hollow container to define a plurality of vertically-stacked liquid treatment chambers, a pouring port for introducing liquid to be treated into an upper portion of the hollow container, a discharge port for removing treated liquid from a bottom portion of the hollow container, a gas vent port for introducing gas into the bottom portion of the hollow container, and a hollow tube connected to each horizontal partition plate and extending a predetermined distance downwardly therefrom. Liquid introduced into the top portion of the hollow container flows from one partition plate to an adjacent lower partition plate through the hollow tube in each partition plate. The movement of the liquid created by this arrangement increases the contact surface area between the liquid and the gas introduced into the hollow container, thus increasing gas dissolution in or removal from the liquid. The effect can be further increased by providing stirrers in each liquid treatment chamber mounted on a rotor shaft driven by a motor.

BACKGROUND OF THE INVENTION

It is important in breeding of aquatic life to quickly supply oxygenrequired for breathing in a breeding liquid and to quickly removeunnecessary carbon acid gas from the breeding liquid. Such dissolving ofthe gas into the liquid or removal (evaporation) of the gas from theliquid relies upon the size of the contact surface area between the gasand the liquid. If the contact surface area is constant, movement of htliquid, that is, stirring of the liquid increases the contact surfacearea, so that dissolving or evaporation quickly occurs. The invention isdirected to stagnate or accumulate the gas into the liquid in aplurality of separated manners thereby increasing the contact surfacearea between the gas and the liquid in a three-dimensional manner and,further, to stir the liquid by a motor located centrally thereby rapidlyincreasing the contact effect.

SUMMARY OF THE INVENTION

It is considered that conditions, under which a gas is dissolved in aliquid, include 1) the kind of the gas, 2) a partial pressure of the gasin the atmosphere, 3) the kind of the liquid, 4) a partial pressure ofthe gas in the liquid, 5) temperature, 6) air pressure, 7) a contactsurface area between the gas and the liquid, and the like.

Whether the gas is dissolved in the liquid or is removed from the liquidis determined by the relationship between a partial pressure of the gasin the atmosphere containing the gas and a partial pressure of the gas(dissolved) in the liquid. That is, if the pressure of the gas in theatmosphere is higher than the partial pressure in the liquid, the gas isdissolved in the liquid and, conversely, if the partial pressure of thegas in the atmosphere is lower than the partial pressure in the liquid,the gas is removed from the liquid. The invention utilizes this physicalphenomenon to efficiently dissolve or remove the gas into or from theliquid by moving the liquid more than the gas to increase the contactsurface area between the gas and the liquid.

The aspect, in which gas is dissolved in water, will be described usingoxygen as an example. Oxygen in a gas is quickly dissolved in a surfaceof the water due to a diffusion phenomenon (this phenomenon is alsodiffusion), but the dissolved oxygen is diffused in the water extremelyslowly. That is, only 0.0001 second or 0.01 second will be required fordiffusion of distances over 1 micron or 10 microns, respectively. If thedistances become 1 mm and 1 cm, however, 100 seconds and 3 hours arerequired, respectively. A stream or flow of the water plays an importantrole in transmitting oxygen to water which is not in contact with theoxygen, so that the dissolving phenomenon due to the above-describedincrease in the contact surface area is explained from another angletheoretically.

A microorganism decomposes organic matter under the separated andaccumulated gas phase for the purpose of hyperplasia of themicroorganism per se under aerobic conditions in the gas phase. Thedecomposing speed is the same as the breeding speed of themicroorganism. This means that, if the microorganism is in contact withsewage having organic matter with the number of individuals to such anextent as to utilize (decompose) a give quantity of organic matters by asingle cell division, it is possible to treat the sewage for 20 to 30minutes. The effect of the oxygen supply in the invention will now bedescribed. Since oxygen starvation can be avoided in a three-dimensionalmanner, that is, since air is accumulated in a multiple stage manner toincrease the contact surface area between the oxygen and the waterinfinitely, it is possible to cope with the oxygen demand of a plethoraof microorganisms to an extent near the infinite, theoretically. Ifstirring due to a motor is added, an effect the same as increasing thecontact surface area occurs so that the oxygen is rapidly supplied.Thus, carbonic acid gas is quickly removed.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood by reference to the accompanyingdrawings, in which:

FIG. 1 is a vertical cross-sectional view of one embodiment of themultiple-gas-phase liquid treatment apparatus in accordance with theinvention; and

FIG. 2 is a vertical cross-sectional view of a modification of theapparatus shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG. 1, a plurality of partition plates 12 are horizontallymounted at constant intervals in a container 10 and, further, a singlehollow tube 14 is attached to each of the plates 12 so as to projectdownwardly. Tubes 14 are arranged in staggered relation to each other atpositions adjacent opposite side walls of the container. The container10 has a pouring port 16 through which breeding water enters, a waterdischarge port 18 through which treated water is taken out, and a ventport 20 through which oxygen or the like is delivered.

FIG. 2 is a vertical cross-sectional view in which a plurality of rotarystirring bars 22 powered by a motor 24 are installed in FIG. 1, to causethe effect of increasing the contact surface area between gas andliquid.

FIGS. 1 and 2, if the water discharge port 18 is closed, if water ispoured through the water pouring port 16 and is accumulated, and if gasis introduced through the below vent port 20, the gas is accumulatedcorrespondingly to the height of the tube 14. The surplus gas ascendsthrough the tube 14 and is again accumulated at the upper partitionplate 12. Here, if the water discharge port 18 is open and if the wateris poured through the water pouring 16, the water descends through thetubes 14, and the gas ascends through the same tubes 14.

The height of each of the tubes 14 prescribes the quantity of the gasphase. It is sufficient that a single tube 14 is provided on a singlepartition plate 12. The tube 14 has a cross-sectional area which shouldbe large when the quantity of flowing water becomes large, or the numberof the tubes 14 should increase if the quantity of flowing water becomeslarge. In the case where a plurality of vertical partitions (not shown)are provided on each partition plate 12 to divide the gas phase, thenumber of tubes 14 (the height of each of the tubes is shorter than thatof each of the vertical partitions (not shown) is required to correspondto the number of the divided gas phases.

In FIG. 1, breeding water flows in a natural fall while being in contactwith gas such as oxygen or the like at an artificial water surface 26 inthe course of the falling down. Since the contact surface area increasesin a three-dimensional manner, the oxygen or the like increases inchance of dissolving. In the case where the oxygen is vented from below,the breeding water is initially in contact with the exhaust gas, but thebreeding water is in contact with fresh oxygen immediately before comingout of the apparatus as treated water. This becomes opposed flow and isreasonable.

In FIG. 2, when the water flows in through the above water pouring port16 and is taken out through the water discharge port 18, the gas entersthrough the below vent port 20 and, further, the water is stirred. Thus,it is possible for the apparatus to obtain water in which the gas israpidly dissolved well. The number of the stirring bars 22 and motors 24increases depending upon the scale and configuration of the apparatus.

In FIGS. 1 and 2, if a mixture of sewage and activated sludge is pouredin place of the breeding water, and if air or oxygen enters from belowthe apparatus, the gas phase is accumulated below each plate 12, and theorganic matter in the sewage is decomposed for a short period of timeunder a condition rich in oxygen. Thus, it is possible to obtain fromthe apparatus sludge water containing low organic matter as treatedwater.

According to the present invention, a multiple-gas-phase liquidtreatment apparatus is provided which is low in cost and which dissolvesand supplies gas in an immediate effect manner or which removes gas inan immediate effect manner. In the case of the use of oxygen, it ispossible to continuously supply breeding water which is useful inbreeding of all aquatic life.

If a culture liquid is substituted for the sewage, and if a usefulmicroorganism is substituted for the activated sludge, a large-quantitycontinuous culture is made possible easily in the apparatus.

If a sugar liquid is substituted for the sewage and if useful yeast issubstituted for the activated sludge, it is possible to obtainfermentation products such as alcoholic drink, beer, low-class distilledspirits, vinegar or the like in the apparatus. In this connection, inconsideration of a period using oxygen as the gas and a subsequentperiod of anaerobic fermentation using no oxygen as the gas, it isrequired to vary the kind of gases to effect control. It is alsopossible to treat the culture liquid in the present apparatus and tocultivate the culture liquid in another tank.

In any event, for any rate of gas used in the invention, it can easilybe understood to enable the gas to be dissolved in the liquid to theextent of saturation in a moment. Conversely, the invention can beoperated in an atmosphere in which a gas in not contained, to evaporateand remove the gas which is dissolved in the liquid. Thus, applicationis very wide.

We claim:
 1. A multiple-gas-phase-liquid treatment apparatus comprisinga container means having a hollow interior including a top portion, abottom portion and opposed side walls interconnecting said top andbottom portions; a plurality of horizontal partition plates mounted insaid hollow interior to define a plurality of vertically-stackedliquid-treatment chambers; pouring port means connected to saidcontainer means for introducing liquid into the top portion of saidhollow interior and onto a top one of said partition plates, dischargeport means connected to said container means for discharging treatedliquid from the bottom portion of said hollow interior, vent port meansfor introducing gas into the bottom portion of said hollow interior, andhollow tube means comprising a hollow tube connected to each horizontalpartition plate and projecting downwardly a predetermined distance fromsaid horizontal partition plate into an adjacent lower liquid treatmentchamber, said hollow tubes being connected to said horizontal partitionplates in staggered relation to each other at positions adjacent saidopposed side walls of said container, whereby liquid introduced into thetop portion of said hollow interior flows from one partition plate to anadjacent lower partition plate through said hollow tube means, liquid inone liquid treatment chamber flowing through the hollow tube of itsrespective horizontal partition plate onto a horizontal partition plateof an adjacent lower liquid treatment chamber, while gas introduced intothe bottom portion of said hollow interior accumulates beneath saidhorizontal partition plates to a height equal to said predetermineddistance, excess gas ascending through said hollow tubes.
 2. Anapparatus as in claim 1 further comprising mechanical agitation meansfor agitating liquid in each of said vertically-stacked liquid treatmentchambers, wherein said mechanical agitation means comprises a rotorshaft extending from the top portion of said hollow interior throughsaid plurality of horizontal partition plates and to said bottom portionof said hollow interior, a plurality of stirrers, each of said stirrersbeing connected to said rotor shaft in one of said liquid treatmentchambers, and motor means mounted on said container means for rotatingsaid rotor shaft.